4 PHP Markdown Lib 1.4.1 - 4 May 2013
9 based on Markdown by John Gruber
10 <http://daringfireball.net/>
16 This is a library package that includes the PHP Markdown parser and its
17 sibling PHP Markdown Extra with additional features.
19 Markdown is a text-to-HTML conversion tool for web writers. Markdown
20 allows you to write using an easy-to-read, easy-to-write plain text
21 format, then convert it to structurally valid XHTML (or HTML).
23 "Markdown" is actually two things: a plain text markup syntax, and a
24 software tool, originally written in Perl, that converts the plain text
25 markup to HTML. PHP Markdown is a port to PHP of the original Markdown
26 program by John Gruber.
28 * [Full documentation of the Markdown syntax](<http://daringfireball.net/projects/markdown/>)
29 - Daring Fireball (John Gruber)
30 * [Markdown Extra syntax additions](<http://michelf.ca/projects/php-markdown/extra/>)
37 This library package requires PHP 5.3 or later.
39 Note: The older plugin/library hybrid package for PHP Markdown and
40 PHP Markdown Extra is still maintained and will work with PHP 4.0.5 and later.
42 Before PHP 5.3.7, pcre.backtrack_limit defaults to 100 000, which is too small
43 in many situations. You might need to set it to higher values. Later PHP
44 releases defaults to 1 000 000, which is usually fine.
50 This library package is meant to be used with class autoloading. For autoloading
51 to work, your project needs have setup a PSR-0-compatible autoloader. See the
52 included Readme.php file for a minimal autoloader setup. (If you cannot use
53 autoloading, see below.)
55 With class autoloading in place, putting the 'Michelf' folder in your
56 include path should be enough for this to work:
58 use \Michelf\Markdown;
59 $my_html = Markdown::defaultTransform($my_text);
61 Markdown Extra syntax is also available the same way:
63 use \Michelf\MarkdownExtra;
64 $my_html = MarkdownExtra::defaultTransform($my_text);
66 If you wish to use PHP Markdown with another text filter function
67 built to parse HTML, you should filter the text *after* the `transform`
68 function call. This is an example with [PHP SmartyPants][psp]:
70 use \Michelf\Markdown, \Michelf\SmartyPants;
71 $my_html = Markdown::defaultTransform($my_text);
72 $my_html = SmartyPants::defaultTransform($my_html);
74 All these examples are using the static `defaultTransform` static function
75 found inside the parser class. If you want to customize the parser
76 configuration, you can also instantiate it directly and change some
77 configuration variables:
79 use \Michelf\MarkdownExtra;
80 $parser = new MarkdownExtra;
81 $parser->fn_id_prefix = "post22-";
82 $my_html = $parser->transform($my_text);
84 To learn more, see the full list of [configuration variables].
86 [configuration variables]: http://michelf.ca/projects/php-markdown/configuration/
89 ### Usage without an autoloader
91 If you cannot use class autoloading, you can still use `include` or `require`
92 to access the parser. To load the `\Michelf\Markdown` parser, do it this way:
94 require_once 'Michelf/Markdown.inc.php';
96 Or, if you need the `\Michelf\MarkdownExtra` parser:
98 require_once 'Michelf/MarkdownExtra.inc.php';
100 While the plain `.php` files depend on autoloading to work correctly, using the
101 `.inc.php` files instead will eagerly load the dependencies that would be
102 loaded on demand if you were using autoloading.
105 Public API and Versioning Policy
106 ---------------------------------
108 Version numbers are of the form *major*.*minor*.*patch*.
110 The public API of PHP Markdown consist of the two parser classes `Markdown`
111 and `MarkdownExtra`, their constructors, the `transform` and `defaultTransform`
112 functions and their configuration variables. The public API is stable for
113 a given major version number. It might get additions when the minor version
116 **Protected members are not considered public API.** This is unconventional
117 and deserves an explanation. Incrementing the major version number every time
118 the underlying implementation of something changes is going to give
119 nonessential version numbers for the vast majority of people who just use the
120 parser. Protected members are meant to create parser subclasses that behave in
121 different ways. Very few people create parser subclasses. I don't want to
122 discourage it by making everything private, but at the same time I can't
123 guarantee any stable hook between versions if you use protected members.
125 **Syntax changes** will increment the minor number for new features, and the
126 patch number for small corrections. A *new feature* is something that needs a
127 change in the syntax documentation. Note that since PHP Markdown Lib includes
128 two parsers, a syntax change for either of them will increment the minor
129 number. Also note that there is nothing perfectly backward-compatible with the
130 Markdown syntax: all inputs are always valid, so new features always replace
131 something that was previously legal, although generally nonsensical to do.
137 To file bug reports please send email to:
138 <michel.fortin@michelf.ca>
140 Please include with your report: (1) the example input; (2) the output you
141 expected; (3) the output PHP Markdown actually produced.
143 If you have a problem where Markdown gives you an empty result, first check
144 that the backtrack limit is not too low by running `php --info | grep pcre`.
145 See Installation and Requirement above for details.
148 Development and Testing
149 -----------------------
151 Pull requests for fixing bugs are welcome. Proposed new features are
152 going meticulously reviewed -- taking into account backward compatibility,
153 potential side effects, and future extensibility -- before deciding on
154 acceptance or rejection.
156 If you make a pull request that includes changes to the parser please add
157 tests for what is being changed to [MDTest][] and make a pull request there
160 [MDTest]: https://github.com/michelf/mdtest/
166 If you wish to make a donation that will help me devote more time to
167 PHP Markdown, please visit [michelf.ca/donate] or send Bitcoin to
168 [1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH].
170 [michelf.ca/donate]: https://michelf.ca/donate/#!Thanks%20for%20PHP%20Markdown
171 [1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH]: bitcoin:1HiuX34czvVPPdhXbUAsAu7pZcesniDCGH
179 * Added the ability to insert custom HTML attributes everywhere an extra
180 attribute block is allowed (links, images, headers). Credits to
181 Peter Droogmans for providing the implementation.
183 * Added a `url_filter_func` configuration variable which takes a function
184 that can rewrite any link or image URL to something different.
187 PHP Markdown Lib 1.4.1 (4 May 2014)
189 * The HTML block parser will now treat `<figure>` as a block-level element
190 (as it should) and no longer wrap it in `<p>` or parse it's content with
191 the as Markdown syntax (although with Extra you can use `markdown="1"`
192 if you wish to use the Markdown syntax inside it).
194 * The content of `<style>` elements will now be left alone, its content
195 won't be interpreted as Markdown.
197 * Corrected an bug where some inline links with spaces in them would not
198 work even when surounded with angle brackets:
200 [link](<s p a c e s>)
202 * Fixed an issue where email addresses with quotes in them would not always
203 have the quotes escaped in the link attribute, causing broken links (and
206 * Fixed the case were a link definition following a footnote definition would
207 be swallowed by the footnote unless it was separated by a blank line.
210 PHP Markdown Lib 1.4.0 (29 Nov 2013)
212 * Added support for the `tel:` URL scheme in automatic links.
214 <tel:+1-111-111-1111>
216 It gets converted to this (note the `tel:` prefix becomes invisible):
218 <a href="tel:+1-111-111-1111">+1-111-111-1111</a>
220 * Added backtick fenced code blocks to MarkdownExtra, originally from
221 Github-Flavored Markdown.
223 * Added an interface called MarkdownInterface implemented by both
224 the Markdown and MarkdownExtra parsers. You can use the interface if
225 you want to create a mockup parser object for unit testing.
227 * For those of you who cannot use class autoloading, you can now
228 include `Michelf/Markdown.inc.php` or `Michelf/MarkdownExtra.inc.php` (note
229 the `.inc.php` extension) to automatically include other files required
233 PHP Markdown Lib 1.3 (11 Apr 2013)
235 This is the first release of PHP Markdown Lib. This package requires PHP
236 version 5.3 or later and is designed to work with PSR-0 autoloading and,
237 optionally with Composer. Here is a list of the changes since
238 PHP Markdown Extra 1.2.6:
240 * Plugin interface for WordPress and other systems is no longer present in
241 the Lib package. The classic package is still available if you need it:
242 <http://michelf.ca/projects/php-markdown/classic/>
244 * Added `public` and `protected` protection attributes, plus a section about
245 what is "public API" and what isn't in the Readme file.
247 * Changed HTML output for footnotes: now instead of adding `rel` and `rev`
248 attributes, footnotes links have the class name `footnote-ref` and
249 backlinks `footnote-backref`.
251 * Fixed some regular expressions to make PCRE not shout warnings about POSIX
252 collation classes (dependent on your version of PCRE).
254 * Added optional class and id attributes to images and links using the same
255 syntax as for headers:
257 [link](url){#id .class}
258 ![img](url){#id .class}
260 It work too for reference-style links and images. In this case you need
261 to put those attributes at the reference definition:
263 [link][linkref] or [linkref]
266 [linkref]: url "optional title" {#id .class}
268 * Fixed a PHP notice message triggered when some table column separator
269 markers are missing on the separator line below column headers.
271 * Fixed a small mistake that could cause the parser to retain an invalid
272 state related to parsing links across multiple runs. This was never
273 observed (that I know of), but it's still worth fixing.
276 Copyright and License
277 ---------------------
280 Copyright (c) 2004-2014 Michel Fortin
285 Copyright (c) 2003-2005 John Gruber
286 <http://daringfireball.net/>
289 Redistribution and use in source and binary forms, with or without
290 modification, are permitted provided that the following conditions are
293 * Redistributions of source code must retain the above copyright
294 notice, this list of conditions and the following disclaimer.
296 * Redistributions in binary form must reproduce the above copyright
297 notice, this list of conditions and the following disclaimer in the
298 documentation and/or other materials provided with the
301 * Neither the name "Markdown" nor the names of its contributors may
302 be used to endorse or promote products derived from this software
303 without specific prior written permission.
305 This software is provided by the copyright holders and contributors "as
306 is" and any express or implied warranties, including, but not limited
307 to, the implied warranties of merchantability and fitness for a
308 particular purpose are disclaimed. In no event shall the copyright owner
309 or contributors be liable for any direct, indirect, incidental, special,
310 exemplary, or consequential damages (including, but not limited to,
311 procurement of substitute goods or services; loss of use, data, or
312 profits; or business interruption) however caused and on any theory of
313 liability, whether in contract, strict liability, or tort (including
314 negligence or otherwise) arising in any way out of the use of this
315 software, even if advised of the possibility of such damage.